i-Tree Design uses the address entered to generate a generic regional list of species. The species list available is based off regional i-Tree Streets climate zones https://www.itreetools.org/streets/imag ... _zones.jpg. You can also see the climate zone related to your address in parenthesis next to the species list drop down in the "Place Trees" dialog frame. In some cases, addresses that are near the border of (2) climate zones may have a different species list. For example, Philadelphia is in the edge of the coastal plain zone and suburbs to the west are in the Northeast zone and will have different tree species available.

This is a characteristic or limitation of the regional modeling approach as cities are classified by zip codes into Streets/Design climate zones, and this may seem inconsistent that towns or cities nearby to each other would have different species available. More sophisticated local modeling tools like i-Tree Eco use one master species list with 7000+ trees/shrubs for all locations, but this would not be practical for a simple tool created for homeowner & school engagement like i-Tree Design.